The John S. McCain, an American guided-missile destroyer, with a hole in its left side, in waters off Singapore on Monday.

BANGKOK — Ten Navy sailors were missing and five were injured on Monday after a United States destroyer collided with an oil tanker off the coast of Singapore, the Navy said, the second accident involving a Navy ship and a cargo vessel in recent months.

The guided-missile destroyer, the John S. McCain, was passing east of the Strait of Malacca on its way to a port visit in Singapore at 5:24 a.m. local time, before dawn broke, when it collided with the Alnic MC, a 600-foot vessel that transports oil and chemicals, the Navy said. The destroyer was damaged near the rear on its port, or left-hand, side.

Ten sailors on the ship were unaccounted for, and five others were injured, a Navy official said. Ships with the Singapore Navy and helicopters from the assault ship America were rushing to search for survivors. Four of the injured were transported by a Singapore military helicopter to Singapore, where they were being treated for conditions that were not believed to be life-threatening. The fifth injured sailor did not require additional medical attention, according to the Seventh Fleet.

While the collision involved a Navy vessel and a commercial tanker, the incident highlighted the geopolitical dangers surrounding the South China Sea, where China has been challenging American naval dominance. It also raised questions about the safety record of Navy ships, since the incident came just two months after seven people were killed when another Navy destroyer collided with a freighter off Japan.

A photo of the John S. McCain showed a gaping hole in its side right at the waterline, but the ship did not appear to be listing.

In a statement, the Navy said the destroyer had reached Changi Naval Base in Singapore. “Significant damage to the hull resulted in flooding to nearby compartments, including crew berthing, machinery and communications rooms,” the statement said. “Damage control efforts by the crew halted further flooding.”

The Alnic MC is registered under a Liberian flag and was built in 2008, according to a marine registry. The tanker, which is now anchored in Singapore for damage assessment, had been struck on the front part of its hull, but none of its crew were injured, according to a statement from the Maritime and Port Authority of Singapore.

No oil leaks have been reported in the area, according to the Singaporean authority.

The Strait of Malacca, between the Malay Peninsula and the Indonesian island of Sumatra, is notoriously difficult to navigate because of congested traffic and episodes of…